From 01175255fd8e3e993353a779f819ec8c0c59137e Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Sat, 13 Aug 2016 12:38:22 -0400 Subject: sched: Remove __schedule() non-standard frame annotation Now that the x86 switch_to() uses the standard C calling convention, the STACK_FRAME_NON_STANDARD() annotation is no longer needed. Suggested-by: Josh Poimboeuf Signed-off-by: Brian Gerst Reviewed-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1471106302-10159-8-git-send-email-brgerst@gmail.com Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel/sched') diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 2a906f20fba7..3d91b63dd2f6 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3381,7 +3381,6 @@ static void __sched notrace __schedule(bool preempt) balance_callback(rq); } -STACK_FRAME_NON_STANDARD(__schedule); /* switch_to() */ static inline void sched_submit_work(struct task_struct *tsk) { -- cgit v1.2.3 From c65eacbe290b8141554c71b2c94489e73ade8c8d Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Tue, 13 Sep 2016 14:29:24 -0700 Subject: sched/core: Allow putting thread_info into task_struct If an arch opts in by setting CONFIG_THREAD_INFO_IN_TASK_STRUCT, then thread_info is defined as a single 'u32 flags' and is the first entry of task_struct. thread_info::task is removed (it serves no purpose if thread_info is embedded in task_struct), and thread_info::cpu gets its own slot in task_struct. This is heavily based on a patch written by Linus. Originally-from: Linus Torvalds Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jann Horn Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/a0898196f0476195ca02713691a5037a14f2aac5.1473801993.git.luto@kernel.org Signed-off-by: Ingo Molnar --- kernel/sched/sched.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel/sched') diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index c64fc5114004..3655c9625e5b 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1000,7 +1000,11 @@ static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) * per-task data have been completed by this moment. */ smp_wmb(); +#ifdef CONFIG_THREAD_INFO_IN_TASK + p->cpu = cpu; +#else task_thread_info(p)->cpu = cpu; +#endif p->wake_cpu = cpu; #endif } -- cgit v1.2.3 From 68f24b08ee892d47bdef925d676e1ae1ccc316f8 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Thu, 15 Sep 2016 22:45:48 -0700 Subject: sched/core: Free the stack early if CONFIG_THREAD_INFO_IN_TASK We currently keep every task's stack around until the task_struct itself is freed. This means that we keep the stack allocation alive for longer than necessary and that, under load, we free stacks in big batches whenever RCU drops the last task reference. Neither of these is good for reuse of cache-hot memory, and freeing in batches prevents us from usefully caching small numbers of vmalloced stacks. On architectures that have thread_info on the stack, we can't easily change this, but on architectures that set THREAD_INFO_IN_TASK, we can free it as soon as the task is dead. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jann Horn Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/08ca06cde00ebed0046c5d26cbbf3fbb7ef5b812.1474003868.git.luto@kernel.org Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel/sched') diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 0b6238f18da2..23c6037e2d89 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2772,6 +2772,10 @@ static struct rq *finish_task_switch(struct task_struct *prev) * task and put them back on the free list. */ kprobe_flush_task(prev); + + /* Task is done with its stack. */ + put_task_stack(prev); + put_task_struct(prev); } -- cgit v1.2.3